Summary

Tarsal tunnel syndrome (TTS) is one of the frequently encountered entrapment neuropathies of the lower limb. Most often the
aetiology is considered to be idiopathic. However, it has to be thoroughly investigated to rule out diverse extrinsic and
intrinsic causes. The sustentaculum tali (ST) forms the superior part of the distal tarsal tunnel, and any increase in its
size may result in irritation of the tibial nerve or its branches, the medial and lateral plantar nerves or decrease the overall
volume of the tarsal tunnel culminating to clinical features of TTS. A hypertrophied ST is an extremely rare cause for TTS,
and we report perhaps a first case of bilateral TTS in a young adult due to bilateral symmetrical hypertrophied ST which in
turn was a result of bilateral fibrous tarsal coalition. Staged bilateral surgical excision of the hypertrophied part of ST
and the underlying fibrous tarsal coalition ensured prompt symptomatic relief.